So recently in our 05 GC we have had a mysterious ding all the time while driving. No light come on the dash at all. They only thing new we notice is CAL comes up during every startup next to the compass. Any ideas of what this ding could be. Any help would be greatly appreciated.

I misread "CAL" as "CEL". Sounds like you need to re-calibrate the compass. Here is that info from the owner's manual:

Quote:

To Put Into a Calibration Mode
Start the engine and leave the transmission in the P (Park)
position. Set the display to “Compass/Temperature.”
Press and hold the C/T button for approximately 5
seconds to change the display to compass variance mode;
holding the button for an additional 5 seconds will flash
the “CAL” symbol indicating compass calibration mode.
When the “CAL” indicator is flashing, complete one or
more 360 degree turns, under 5 mph (8 km/h), in an area
free from large metal objects or power lines. The “CAL”
indicator will turn off and the compass will function
normally.

well guys no luck i calibrated the compass. I also tried to retrive codes and just got message done. One day i get off early from work i am going to the dealer and see if they get any codes for any malfunctions. Come to think of it when i had the duratracs put on the tire place said one of the sensors needed to be replaced but he could maybe make it work. do you think that's whats making it ding just so quick that no lights come up.